Electrolytic meter.



J. N. TUTTLE.

ELECTROLYTIC METER.

APPLICATION FILED OCT. 11. 1912.

1,156,826. Patented Oct. 12, 1915.

Witnesses lm/Gnb or W James N .Tuttle Q e WQM;

JAMES NORWOOD TUTTLE, OIE H-AEWICHPORT, 1VJ IASSAC'HUSETTS, ASSIGNCR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTROLYTIC METER.

Specification of Letters Patent.

Patented 0a. 12, 1915.

Application filed. October 11, 1912. Serial No. 725,219.

To all whom it may concern: Be it known that I, JAMES Nonwooo TUTTLE, a citizen of the United States, re-

siding .at Harwichport, county of'Barnsta ble, State of Massachusetts, have invented certain new and useful Improvements in Electrolytic Meters, of which the following is a specification.

My invention relates to electric meters,

type of electrolytic meter in which the anode is a body of mercury. Meters of this type generally consist of a suitable vessel for the electrolyte and a container for the mercury anode located in the upper part of the vessel and above the cathode.

More particularly my invention has reference to that type of electrolytic meter disclosed in the patent to E. lVeintraub, No.

1,006,612, granted October 21, 1911, and in. which the mercury anode is separated from' the electrolyte by a diaphragm having suff ficient strength to sustain the weight of the mercury and capable of resisting the action of the electrolyte. 1 r

The objects of my invention are to gen: erally improve the construction of this type of meter, and more-specifically to provide a diaphragm for electrolytic meters which will be more satisfactory and efiicient than those which have heretofore been employed or proposed.

A further. object of my invention is to provide a cathode of novel construction.

The novel features which I believe to be characteristic of my invention, will be definitely indicated in the claims appended hereto. 7

The details of construction and mode of operation will be understoodiby reference to the following description taken in connection with the accompanying drawings, which show the preferred embodiments of my 1nvention and in which, I

Figure 1 is a diagrammaticyiew of my improved electrolytic meter; Fig. 2 is an elevation of my novel form of cathode; Fig. 3 is a plan view partly in section of the cathode shown in Fig. 2; Fig. 4: is an elevation of a modified form of cathode, and Fig.

. 5 is aplan view partly in section of the cathode shown in Fig. 4.

Referring first toFig. 1 of the drawings, there is shown a vessel 6, preferably of glass,

containing a suitable electrolyte 7. A fall tube-8 depends from the lower end of the vessel 6. "The fall tube is considerably smaller indiameter than the vessel 6 and is I graduated, as shown in Fig. 1, to enable an accurate and ready means of measuring the deposited mercury. A permanent record chamber 9 is in operative relation to the fall tube and is adapted to contain the mercury which is emptied from the fall tube 84 The upper edge of the vessel 6 is enlarged and tapered, as shown at 10, and is adapted to register with a similarly tapered edge 11 of a cover 12. The registering surfaces of' the edges 10 and 11 are preferably ground to form an air-tight joint between the vessel 6 and the cover 12. r

The vessel 6 is'provided with a partition 13 having a central opening 1 1 and short vertical tubes 15 and 16. The tubes 15 and 16 permit the return of mercury to the anode chamber when the fall tube and permanent record chamber have become filled. This is accomplished by inverting the meter. The

, opening 14: has an upwardly extending shoulder which affords a' convenient means for securing a diaphragm 17 in position to cover the opening 141. Thediaphragm is stretched tightly across the opening 11 and is secured in place by a tie-Wire 18, preferably of platinum. The partition 13 and diaphragm 17 serve to support the mercury anode 19, which is electrically connected to the positive terminal of the meter by a leading-in wire 20.

The diaphragm 17 must be permeable to I the electrolyte and impermeable to mercury. In' accordance with my invention, the diaphragm is composed of a finely woven fabric, the material of the fabric being per meable to the electrolyte and impermeable to mercury, and further'unail'ected byand not contaminating the electrolyte, and still further having little or no tendency to shrink when placed in the electrolyte. The weave of the fabric is fine enough to give ample support to the mercury anode, and yet because of capillaryaction, due to the porosity of the fabric material, a circulation of the electrolyte through the fabric is permitted. I

Fabric woven from silk fulfils-all the requirements of a satisfactory diaphragm, since silk is not attacked by the meter electrolyte, does not contaminate the electrolyte as it can be easily freed of foreign material by washing in boiling water, and further shrinks little, if any, when placed in the electrolyte. I have found finely woven bolting cloth with a mesh of 200K275 per square inch admirably suited for this purpose. The individual fibers of such a fine weave are so near together that the cloth becomes practically a continuous sheet of fibers which possesses all the desirable characteristics of both an osmotic membrane and a porous diaphragm.

Fabrics differ materially from the grid or gauzes which have been previously used as diaphragms, since in the latter the orifices of the grid are absolutely essential to the successful operation of the meter, as the material of the grid is impervious to the electrolyte. With fabric, however, the necessity fororifices is absent and it is desirable to secure as fine a weave as possible and thus practically eliminate the orifices. This results from the fact that the fabric itself acts as an osmotic substance and permits the passage of mercury ions therethrough.

The cathode 21 is of novel construction and consists of a body of mercury positively maintained upon a support of non-conducting material, such as glass, by means of an inclosing diaphragm. In Figs. 2 and 3, I have shown a construction of cathode which comprises a solid glass rod 22 having mercury receptacles consisting of recesses or grooves 23, preferably diametrically located. These receptacles are filled with mercury 24, which is retained in place by means of finely woven fabric, such as bolting cloth, 25, sewed tightly aroundthe rod. A leading-in wire 26 is sealed into the rod and serves to conduct the current from the mercury cathode to the negative terminal of the meter.

A modified construction of cathode is shown in Figs. 4i and 5, and consists of a tubular glass ring 27 having openings 28 on the outer surface of the ring. The interior of the ring constitutes a receptacle and is filled with mercury 29, which is retained within the tube by means of fabric 30 wrapped around the ring and covering the openings 28. The leading-in wire 26 is sealed into the ring as in the construction shown in Figs. 2 and 3. The effective surface area of the recesses 23 and the openings 28 will be so proportioned that the proper current density is obtained. This area should be at least as large as the area of the eifective anode surface.

As the current passes from the positive terminal to the negative terminal of the meter, the mercury ions travel to the cathode, and passing through the orifices of the fabric are deposited upon the mercury of the cathode. As the quantity of the cathode mercury is fixed, mercury from the electrolyte can deposit thereon only until the orifices of the fabric have become filled, and this deposited mercury must fall off in drops, the size of which is determined by the size of the orifice. Since there are some l0,000 orifices to the square inch in fabric having 200 meshes per linear inch, it will be seen that mercury will fall from the cathode in an almost invisible rain.

l/Vhere the fabric has 200 meshes to the linear inch each orifice in the fabric will be about 1/400 of an inch in diameter. The recesses 23 of the cathode support are entirely full of mercury when the meter is placed in operation. The surface tension of the mercury prevents it from escaping through the small orifices in the fabric. As current is passed through the meter the mercury separating from the electrolyte tends to unite with the mercury in the recesses of I the cathode support, but as these recesses are already full no mercury can get in. The deposited mercury can, however, attach itself to the mercury which is exposed through the orifices of the fabric. This it does, and as soon as a drop has collected as large as the orifice in the fabric, it is gradually forced out, as it grows in size, until finally it detaches itself from the main body of mercury and falls off. Since the orifices are only 1/400 of an inch in diameter the drops of mercury have about the same diameter and are almost invisible to the naked eye as they fall through the electrolyte.

The operation of my improved meter will be readily understood from the foregoing description.

WVhile I have illustrated and described the preferred form of my invention, it is obvious that many changes may be made in the details without departing from its spirit and scope, and I accordingly aim to cover in the appended claims all such modifications.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. In an electrolytic meter having a mercury anode, an electrolyte, and a diaphragm forming a support for the mercury anode, said diaphragm being finely woven of a material permeable to, unaffected by and substantially non-shrinking in said electrolyte.

2. In an electrolyte meter having a mercury anode, an electrolyte, and a diaphragm of silk forming a support for the mercury anode, said diaphragm beingpermeable to the electrolyte and impermeable to mercury.

In an electrolytic meter having a mercury anode, an electrolyte, and a diaphragm of bolting cloth forming a support for the mercury anode.

4:. An electrolytic meter having a mercury anode, an electrolyte, and a diaphragm of finely Woven silk fabric separating the mercury anode and the electrolyte.

5. An electrolytic meter having a mercury anode, an electrolyte, a mercury cathode, and a diaphragm of silk separating the mercury cathode from the electrolyte, said diaphragm being permeable to the electrolyte and impermeable to mercury.

6. An electrolytic meter having a mercury anode, an electrolyte, a mercury cathode, and a diaphragm of finely Woven silk fabric separating the mercury cathode from the electrolyte.

7 An electrolytic meter having a mercury anode, an electrolyte, a mercury cathode, and diaphragms of silk separating the 'mercury anode and the mercury cathode from the electloyte, said diaphragms being permeable to the electrolyte and impermeable to mercury.

8. A cathode for electrolytic meters comprising a support of non-conducting material having a mercury receptacle on its surface, mercury in said receptacle, and a diaphragm of silk covering said receptacle and secured to said support for maintaining the mercury Within the receptacle.

9. A mercury cathode for electrolytic meters comprising a non-conducting support having recesses therein, mercury in said recesses, and finely Woven silk fabric secured to said support and covering said recesses and adapted to maintain the mercury Within the recesses.

10. A mercury cathode for electrolytic meters comprising a non-conducting supporting member having a receptacle on the Gopies of this patent may be obtained for surface thereof, mercury in said receptacle, and a covermg of finely Woven fabric of a .tainer, a body of mercury forming the anode of said meter supported by and separated from the electrolyte by said diaphragm, a

cathode mounted in said container beneath said diaphragm, and a fall-tube adapted to receive the mercury deposited at the cathode.

12. An electrolytic meter comprising a container for the electrolyte, a member having a central opening in said container, a diaphragm of finely Woven fabric covering said opening, a body of mercury forming the anode of said meter and supported by said member and separated from said electrolyte by said fabric,a mercury cathode in said container and beneath said opening and consisting of a non-conducting support having a mercury receptacle on its surface, Inercury in said receptacle, means for maintaining sald mercury in said receptacle, and-a fall tube adapted to receive the niercury deposited at the cathode.

In Witness' vhereof, I have hereunto set my hand this ninth day of October, 1912. JAMES NORWOOD TUTTLE. Witnesses:

ROBERT 'Si-IAUT, JOHN A. MCMANUS, Jr.

Washington, .D. G.

five cents each, by addressing the f-Gommissioner of Patents, 7 

